Rubber composition



Patented May 19125.

UNITED (STATES.

- FREDERICK a. MAYWALD, or NUTLEY, NEW JERsEY.'

. RUBBER comr'osrrrou.

No Drawing.

To all whom it my co'ncem; Be it known that I, FREDERICK J MAY- WALD, acitizen of the United States, residing at Nutley, in the county ofEssex. and 6 State of'New- Jersey, have invented certain newand usefulImprovements in Rubber Compositions; and I do 'hereby declare thefollowing to bee full, clear, and exact de-. scription of the invention,such as will enable others skilled in the art to which it appertains tomakeand use the same.

This invention relates 'to an improved composition for useinmanuf'acturing rubber-goods and articles of various kinds.

' The principal objects of the invention are to provide a rubbercomposition which yields'a finished product, when cured, possessingunusual tensile strength; a composition which produces betternon-oxidizing '20 qualities in both the uncured and cured stocks and acomposition which is cheaper than the; heretofore known compoundssuitable for'the production of corresponding products.

I the genus Sapotacea, its species being 1111 40. identifiedbotanically, butxwhich is locally known where found as the" Sandee tree;the

latter is to be found in tropical zones, es- ;pecially in Colombia andEquador, South America. The composition thus provided yields a product,when cured, having a much greater tensile strength and stretch than thesame rubber compound without the Sandee gum content would provide. Thepresence of the Sandee gum in such a composition I 66 also acts as asoftener for the rubber com pound, and is; therefore, a very desirableaddition to rubber compounds used for frictioning and skimming purposes,such as in her object of theinvention i'sto provide a composition whichcan success-.

' Application filed August 31, 1921. Serial m. 497,414.

the production of pneumatic tires, belting, hose and allied products;

The presence of the Sandee gum in the 'rubber compound promotes thesuccessful working of the latter on tubing machines, and While in noway. retarding the cure, yields aproduct which tubes very easily andfreely, and finishes with a clean smooth sur-' face.

The Sandee gum can with advantage be successfully employed .as asubstitute or in place of Pontianac, J elutong, Accra Flake and similarsoft rubbers in rubber compounds. The advantages ofiered by such use.over said soft rubbers are that Sandee gum by it self. ages well anddoes'not bekind above mentioned; and'the same can be.

Washed, dried and stored successfullywith a minimum liability todeterioration. Furthermore, approximately one-half as much Sandee gum isrequired in a compound or composition designed to produce a given degreeof softness and fr-ictioning qualities as would be required if Jelutongor similar rubbers were used in such compound or composition, while atthe same time an increase of tensile strength from twenty-five to fiftyper cent over the corresponding Jelutong or similar compound isobtained.

t The presence of Sandee gum inthe composition produces in theunvulcanized'com pound and frictionin'g stocks a tendency againstblooming.

The relative proportions of Sandee gum and pure rubber gum or rubbercompound in a given composition are dependent upon the degree ofsoftness or flexibility required of the product, and consequently theformulae,as to such relative pro ortions, are.

the advantage of combining with a pure rubber gum or rubber compound apro-portion of Sandee gum, the same being an entirely new ingredient,and consequently conceive my invention toib'e, broadly, the reture ofSan ee gum and pure rubber gum admixture of pure rubber gum compoundorrubber compound regardless of the exactand Sandee'gum.

' I sultant COIHSOSltiOlI comprising an adinixgree of softness andflexibility comprising an relative proportions employed. In fact Intestimony that I.claiin the invention 6 I claim 2- I set forth above Ihave hereunto setmy hand 15 1. A- vulcanizable composition comprisis hday Of August, '1921.

ing an admixture with a pure rubber gum FREDERICK J. MAYWALD. compound,of Sandee gum. Witnesses: v 2. A. composition for producin rubber GEORGED. RICHARDS,

10- product-shaving a comparatively 'gh de- Eva E.

